Hmm I thought that, but we don't really live in a 3D world (or use the altitude parameter in a very meaningful way in life) so I wondered whether there's something else I was missing.
I wonder what makes you belittle the altitude dimension? Buildings have storys, humans can sit and stand, birds can fly, your eyes can move up and down your monitor.
Visiting Chongqing city felt quite 3D to me
If you lived in a high place (Denver), you will find it different from a flat lowland (Chicago).
Also in Rio, how high you live can be a marker depending on which part of town you are. Favelas are on hills, whereas wealthy people in Zona Sul live down the hill closer to the beaches.